Communications by way of cellular communication systems, e.g., is pervasive and, in some areas, the number of users of cellular communication systems approaches, or exceeds, the number of users of conventional, wireline communication systems.
Successive generations of cellular communication systems have been developed and deployed. Additionally, other mobile communication systems that share some of the characteristics of cellular communication systems have also been developed and deployed. Wireless local area networks (WLANs) are mobile communication systems that operate, at least in some manners, analogous to operation of cellular communication systems. Some WLANs are constructed to be operable in general conformity with the IEEE 802.11 family of standards. Wireless local area networks are generally implemented as small-area systems that encompass areas generally smaller than the areas encompassed by cellular communication systems.
Various standard promulgations are under consideration and others have been added to the existing set of standards. For instance, technical standard TS 33.102 [1] version 7.4.0 pertains to I-WLAN (interworking wireless local area network) selection. The wireless device, viz., the user equipment, is sometimes positioned at a location that is encompassed by the coverage areas of more than one wireless local area network. Selection must be made of with which, if any, of the WLANs that the UE shall communicate. The aforementioned technical specification defines a user controlled WLAN specific identifier list (EF-UWSIDL) and an operator controlled WLAN specific identifier list (EF-OWSIDL). The lists form files that are stored at the UE, e.g., at the (U)SIM or in memory or copied from the (U)SIM into the UE memory. And, the identifiers of the list or lists stored at the UE are accessed and used in the selection process. The files have two fields, the first of which identifies the total length of the file and the second is the SSID (Service Set Identifier), coded as binary.
An SSID is an element of a length of between 0 and 32 bytes. A potential problem with the existing technical standard promulgation results as it presently is not possible to determine how many SSIDs have been coded on the (U)SIM for the reason that the SSIDs are not of fixed lengths, but, rather, are of any of the 0-32 byte lengths. The UE that accesses and reads the data forming the relevant WSID list is at risk of incorrectly decoding the stored information.
Additionally, technical specification TS 24.234, which also pertains to network selection, requires that at least ten SSIDs shall be storable at the relevant WSID list. However, only one byte is allocated to define the length. As a result, only 256 bytes can exist in the file. If the SSIDs are all of thirty-two byte lengths, only eight entries are storable, contrary to the requirements of the TS 24.234 specification.
A manner is therefore required by which better to store the data forming the WSID list, or other specific network identifier list so that an appropriate number of entries are storable thereon while also permitting the UE, or other wireless device, to decode the stored data.
It is in light of this background information related to network selection in a radio communication system that the significant improvements of the present invention have evolved.